This invention relates to an electronic musical instrument, more particularly an electronic musical instrument provided with a plurality of keyboards each having a plurality of keys, and an intermanual performance arrangement.
A so called 4-keyboard type electronic musical instrument has been known which in addition to a main musical tone generating system constituted by a main keyboard section comprising an upper keyboard, a low keyboard and a pedal keyboard, and a main musical tone signal generating section which generates musical tone signals associated with the tone pitches of the depressed keys in the main keyboard section, includes a solo keyboard section for performing a solo, and a solo musical tone signal generator which generates musical tone signals related to the tone pitches of the depressed keys in the solo keyboard section. In an electronic organ of this type, it is possible to preset the solo musical tone signal generating section to be of a suitable tone color for performing a solo independently of the main musical tone signal generating system by independently constructing the solo musical tone generating system including the solo keyboard and the solo musical signal generator from the main musical tone generating system thereby enabling transfer between the main performance and the solo performance during the performance as well as an ensemble of the main and solo performances.
According to one method of intermanual coupling, the solo performance can be made by using the upper keyboard or the lower keyboard (or the pedal keyboard). Such intermanual coupler can be realized by supplying the key information of the upper or lower keyboard (or pedal keyboard) to the solo musical tone signal generating system instead of the key information of the depressed keys of the solo keyboard section. Supply of the key information of one of the keyboards can be suitably selected by a coupler keyboard selection switch. For example, when the coupler keyboard selection switch is thrown to the solo keyboard, it is possible to perform a solo melody on the solo keyboard, and a back chorus on the upper or lower keyboard. Thus, an ensemble of solo performance on the solo keyboard and a back chorus performance on the upper or lower keyboard. Where the coupler keyboard selection switch is set to the upper keyboard, a melody performance on the upper keyboard with an accompaniment performance on the lower keyboard will result in prominence of the melody as a solo performance tone to improve the sound effect. Further, when the coupler keyboard selection switch is set to the lower keyboard, it is possible to enhance the chord performance on the lower keyboard with a counter melody in the solo tone. Where the coupler keyboard selection switch is set to the pedal keyboard, it is possible to enhance the bass tone performance on the pedal keyboard with a solo performance (a solo bass or a walking bass) to improve the sound effect. Especially in the last mentioned case, the solo bass performance can be treated as a melody to emphasize the bass tones.
The intermanual coupler of the electronic musical instrument described above, however, was merely used to supply the key information of the keyboard selected by the coupler keyboard selection switch to the solo musical tone signal generating section so that it is necessary to operate the coupler keyboard selection switch at each time in order to change the condition of the intermanual coupler (to change the correspondence of the solo musical tone signal generating section to a selected keyboard). Accordingly, it is extremely difficult to change the condition of the intermanual coupler during performance.